Temporary retention device

ABSTRACT

A retention device for anchoring indwelling catheters, sheath introducers, feeding tubes, ostomy bags or other medical devices beneath the skin of a patient includes an deployable section coupled to a medical device; following introduction into a patient, the deployable section is subcutaneously deployed, securely anchoring the device and coupled medical device for the duration of treatment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/562,770 filed on Nov. 22, 2006 by Rosenberg et al. and entitled“TEMPORARY RETENTION DEVICE,” which is a continuation of U.S. patentapplication Ser. No. 11/085,016 filed on Mar. 18, 2005 by Rosenberg etal. and entitled “TEMPORARY RETENTION DEVICE,” which is acontinuation-in-part of and claims the benefit of International PatentApplication PCT/US03/15144 filed May 14, 2003 and entitled “SUTURELESSRETENTION DEVICE,” which is a continuation of and claims priority toU.S. patent application Ser. No. 10/383,903 filed on Mar. 7, 2003 byRosenberg et al. and entitled “SUTURELESS RETENTION DEVICE,” now U.S.Pat. No. 6,695,861, which claims priority to U.S. Provisional PatentApplication Ser. No. 60/412,453 filed on Sep. 20, 2002, all of which areherein incorporated in their entirety.

FIELD OF THE INVENTION

The invention relates to a device for securing in-dwelling catheters,sheath introducers, feeding tubes, ostomy bags, pacing leads or othermedical devices to patients.

BACKGROUND

Medical treatments requiring the delivery or drainage of varioussolutions such as antibiotics, cancer drug therapy, blood draws,abscessed biliary material or urinary tract fluids, rely upon a medicaldevice such as indwelling catheters or sheath introducers to be insertedinto the patient for an extended period of time such as thirty or evensixty or ninety days at a time. Additional procedures requiring othermedical device such as feeding tubes, ostomy bags, or pacing leadssimilarly require introduction and continued placement for extendedperiods. A requirement for maintaining the medical device within apatient for such a period is that the medical device be secured so asnot to move excessively during treatment.

Typically the physician creates an incision or puncture through thepatient's skin with the goal of reaching an artery, vein, other vesselor anatomical site to allow insertion of the medical device at aspecific anatomical site. Currently many temporarily implanted medicaldevices are secured utilizing a tab or eyelet formed in the medicaldevice through which a suture is taken through the tab and skin. Astandard 2-0 suture is most often used for this purpose, which is tiedoff thus securing the catheter within the patient's body. Suturing sucha device to a patient, however, presents several problems: (1) Suturinga medical device to a patient's body makes it difficult to clean anddisinfect the area around the insertion point, resulting in a high rateof infection in the area close to the device's insertion; (2) Themedical device is subject to being dislodged from the patient followingintroduction resulting in migration of the medical device duringtreatment; and (3) A sutured medical device is subject to a disorientedpatient ripping the medical device loose and tearing the suture out.This can result in patient injury and often necessitates costlyreplacement or additional corrective procedures.

An additional disadvantage of suturing a medical device to a patient ispain and discomfort to the patient during the period of treatment, as aresult of a long-term suture extending through the patient's skin.Further, different physicians use different suturing and knottingtechniques, resulting in a wide variation of pull strengths required torip out and dislodge the sutured medical device from the patient's body.

Another securement method utilizes adhesive tape. In this method a layerof tape is placed over a cleaned external site on the patient's bodyafter medical device insertion has been accomplished. The medical deviceis adhered to the skin by adhesive friction. This method is ineffectiveat reducing the incidence of infection. Further, it does not prevent theinadvertent and sometimes violent removal of the medical device prior tocompletion of treatment.

What is therefore needed is a retention device for medical devices thatallows for simple and effective anchoring to the patient's body and alsoreduces the incidence of infection, migration and dislodgment.

SUMMARY

In one aspect the retention device comprises a device for subcutaneouslyanchoring a coupled medical device within a patient. The device has adistal section and a proximal section with a deployable section attachedproximate the proximal section. When the device is introduced thedeployable section when deployed deploys subcutaneously in acontrollable manner. In another embodiment the device has the deployablesection attached to a platform with the deployable section capable oftransitioning between a first configuration proximate the platform and asecond configuration extending from the platform.

In another aspect the retention device comprises a device forsubcutaneously anchoring a coupled medical device within a patient andhas a restraint and an anchor mechanism contacting the restraint. Atleast a portion of the anchor mechanism is capable of transitioningbetween a first configuration when restrained by the restraint and asecond configuration when unrestrained by the restraint. The anchormechanism has at least a single extension and at least a portion of theextension is capable of flexibly and repeatedly moving between the firstconfiguration and the second configuration. The device defines a distalsection and a proximal section, with the restraint and anchor mechanismproximate the proximal section. Separating the anchor mechanism and therestraint from each other unrestrains the extension in a gradual andcontrolled manner, thus causing the extension to gently transition fromthe first configuration toward the second configuration. In oneembodiment the restraint is fixed and the anchor mechanism is movable sothat at least a portion of the extension of the anchor mechanism canmove toward the unrestrained second configuration. In an alternativeembodiment, the anchor mechanism is fixed and the restraint is capableof moving to allow at least a portion of the extension of the anchormechanism to move toward the unrestrained second configuration.

In yet another aspect, the retention device comprises a device forsubcutaneously anchoring a coupled medical device within a patient. Thedevice has an anchor sleeve with a chamber defining at least a singleport. An anchor mechanism is movably loaded into the chamber, with theanchor mechanism capable of moving between a restrained firstconfiguration and an unrestrained second configuration. The anchormechanism has at least a single tine having a first end and a secondfree end, and the second end of the tine is capable of flexibly andrepeatedly moving between the first configuration and the secondconfiguration. The tine has a trained shape when in the secondconfiguration, with the length of the tine such that the tine isrestrained within the chamber when the anchor mechanism is in the firstconfiguration. The port is sized and located so the free end of the tineis proximate the port when the tine is in the first configuration.Biasing means are provided to move the anchor mechanism into the secondconfiguration. A removable actuation key is sized to fit into the anchorsleeve to contact the anchor mechanism. When the key is inserted intothe anchor sleeve the anchor mechanism moves from the secondconfiguration and is retained in the first configuration which causesthe second end of the tine to enter the chamber through the port.

In still another aspect, the retention device comprises a device forsubcutaneously anchoring a coupled medical device within a patient. Thedevice has an anchor sleeve with a chamber defining a longitudinal axisand at least a single port. An anchor mechanism is movably loaded intothe chamber, with the anchor mechanism capable of moving between arestrained first configuration and an unrestrained second configuration.The anchor mechanism has at least a single loop capable of extendingfrom the port and the loop is capable of repeatedly moving between thefirst configuration and the second configuration. The loop has a trainedshape when in the second configuration. Biasing means are provided tomove the anchor mechanism into the second configuration. A key is sizedto fit into the anchor sleeve to contact the anchor mechanism, whereinserting the key into the anchor sleeve moves the anchor mechanism fromthe second configuration to the first configuration causing the loop toenter the chamber through the port.

In an alternative aspect the retention device comprises a device forsubcutaneously anchoring a coupled medical device within a patient. Thedevice has an inner sheath defining an outer dimension and an outersheath defining an inner dimension, with the outer dimension of theinner sheath sized to slidably fit inside the inner dimension of theouter sheath. The outer sheath defines a sliding end, with the slidingend being movable along the inner sheath. A braid defines a length and awidth, with the braid being attached at a first point to the sliding endof the outer sheath and at a second point to the inner sheath. The braidis capable of moving between an elongated configuration having a greaterlength and a lesser width and a shortened configuration having aninverse relationship between length and width. When the sliding end ofthe outer sheath is moved the full distance of its travel from the pointof braid attachment on the inner sheath, the braid assumes the elongatedconfiguration and the device can be introduced or removed from thepatient. When the sliding end of the outer sheath is moved in adirection toward the point of braid attachment on the inner sheath, thebraid moves toward the shortened configuration and the braid defines awidest circumference. In a further embodiment, the braid is coated withan elastomeric coating.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, identical reference numerals indicate identical orequivalent structure where:

FIG. 1 is a side view of an embodiment of the retention device followinginsertion through a patient's skin.

FIG. 2 is a side view of an embodiment of the invention with an anchorsleeve and anchor mechanism attached to an introducer sheath capable ofreceiving and securing a catheter, prior to the tine being deployed.

FIG. 2 a is a cross sectional view taken through the lines 2 a-2 a ofthe embodiment of the invention shown in FIG. 2, with the anchormechanism loaded into the anchor sleeve, prior to deployment.

FIG. 2 b is a cross sectional view taken through the lines 2 a-2 a ofthe embodiment of the invention shown in FIG. 2 with the anchormechanism loaded into and deployed from the anchor sleeve.

FIG. 3 is a side view of an embodiment of the invention with the anchorsleeve and anchor mechanism attached to a dual lumen catheter body andhub.

FIG. 4 is a cross sectional view taken between points 4-4 of theapparatus shown in FIG. 3.

FIG. 5 is a top view of the embodiment of the invention shown in FIG. 3.

FIG. 6 a is a side view of an embodiment of the anchor mechanism.

FIG. 6 b is a side view of an embodiment of the anchor mechanism havingtapered tines.

FIG. 7 is a proximal end view of the embodiment of the anchor mechanismshown in FIG. 6 a.

FIG. 8 is a side view of an embodiment of the anchor mechanism.

FIG. 9 is a side view of an embodiment of the anchor mechanism.

FIG. 10 is a cut away view of an embodiment of the retention deviceshowing the lock mechanism prior to deployment of the tines and showingthe key inserted into the recess.

FIG. 10 a is a cut away view of an embodiment of the retention deviceshowing the lock mechanism following deployment of the tines and the keyinserted prior to unlocking the lock mechanism.

FIG. 11 is a cut away view of an embodiment of the retention deviceshowing the lock mechanism following deployment of the tines with thekey removed from the recess.

FIG. 12 is a partial cut away view of an embodiment of the anchormechanism loaded into the embodiment of the retention device shown inFIG. 2 prior to deployment of the tine.

FIG. 13 is a partial cut away view of an embodiment of the anchormechanism loaded into the embodiment of the retention device shown inFIG. 2 following deployment of the tine.

FIG. 14 is a cut away view of an embodiment of the retention deviceshowing the lock mechanism prior to deployment of the tines.

FIG. 15 is a cut away view of an embodiment of the retention deviceshowing the lock mechanism following deployment of the tines.

FIG. 16 is a side view of an embodiment of the retention device showingthe anchor mechanism in phantom and the locking mechanism in a cut awayview.

FIG. 17 is a cross sectional view taken through the lines 17-17 of theembodiment of the retention device shown in FIG. 16.

FIG. 18 is a cut away side view of an embodiment of the retention deviceshowing a separate spring and the anchor mechanism in the undeployedconfiguration.

FIG. 18 a shows a cross section of the embodiment of the retentiondevice shown in FIG. 18 taken through points 18 a-18 a.

FIG. 18 b is a cut away side view of the key and a portion of the anchorsleeve, in the undeployed configuration, with the key inserted.

FIG. 19 is a cut away side view of the embodiment of the retentiondevice shown in FIG. 18 in the deployed configuration.

FIG. 19 a shows the anchor mechanism of the embodiment shown in FIG. 19removed from the retention device.

FIG. 19 b is a cut away side view of the key and a portion of the anchorsleeve, in the deployed configuration, with the key removed.

FIG. 20 is a cut away side view of an embodiment of the retention devicesimilar to the device shown in FIG. 18, but showing an attached spring.

FIG. 20 a is a side view of the anchor mechanism with attached springused in the embodiment shown in FIG. 20, removed from the retentiondevice.

FIG. 20 b is a cross section of the embodiment of the retention deviceshown in FIG. 20 taken along the line 20 b-20 b.

FIG. 21 is a cut away side view of an embodiment of the retention devicesimilar to the device shown in FIG. 18 showing a spring integrallyattached to the anchor mechanism.

FIG. 21 a is a side view of the anchor mechanism of the embodiment shownin FIG. 21 removed from the retention device.

FIG. 22 is a cut away side view of an embodiment of the retention devicein the deployed configuration.

FIG. 22 a is a side view of the anchor mechanism of the embodiment shownin FIG. 22 removed from the retention device.

FIG. 23 is a cut away side view of the embodiment of the retentiondevice shown in FIG. 22 in the undeployed configuration.

FIG. 24 is a partial cut away side view of an embodiment of theretention device in the deployed configuration, with the coated braid inthe shortened symmetrical configuration.

FIG. 25 is a partial cut away side view of the embodiment of theretention device shown in FIG. 24 in the undeployed configuration, withthe coated braid in the elongated configuration.

FIG. 25 a is a cross section taken along the line between points 25A-25Aof FIG. 25.

FIG. 26 is a partial cut away side view of an embodiment of theretention device in the deployed configuration, with the braid in theshortened 45 degree/45 degree asymmetrical configuration.

FIG. 27 is a partial cut away side view of an embodiment of theretention device in the deployed configuration, with the braid in theshortened 60 degree/30 degree asymmetrical configuration.

FIG. 28 is a partial cut away side view of an embodiment of theretention device in the deployed configuration, with the uncoated braidin the shortened 90 degree symmetrical configuration.

FIG. 29 is a partial cut away side view of the embodiment of theretention device shown in FIG. 28 in the undeployed configuration, withthe uncoated braid in the elongated configuration.

FIG. 29 a is a cross section taken along the line between points B-B ofFIG. 28 showing the uncoated braid.

FIG. 30 is a cut away side view of an embodiment of the retention devicehaving an anchor mechanism made from cut tubing in the deployedconfiguration.

FIG. 30 a is a side view of the anchor mechanism of the embodiment shownin FIG. 30, removed from the invention.

FIG. 30 b is a top end view of the anchor mechanism of the embodimentshown in FIG. 30, removed from the invention.

FIG. 31 is a cut away side view of an embodiment of the retention deviceshown in FIG. 30 in the undeployed configuration.

FIG. 32 is a side view of an embodiment of the retention device having amovable, externally mounted anchor mechanism in the undeployedconfiguration.

FIG. 32 a shows a cross section of the embodiment shown in FIG. 32 takenthrough the lines 32 a-32 a.

FIG. 32 b shows a cross section of the embodiment shown in FIG. 32 takenthrough the lines 32 b-32 b.

FIG. 33 is a side view of the embodiment shown in FIG. 32 in thedeployed configuration.

FIG. 34 is a cut away side view of an embodiment of the retention devicehaving a fixed, externally mounted anchor mechanism in the undeployedconfiguration.

FIG. 35 is a cut away side view of the embodiment shown in FIG. 34 inthe deployed configuration.

FIG. 36 is a side view of the embodiment of the retention device shownin FIGS. 18-19 b attached to a sheath introducer following introductionand subcutaneous deployment.

DETAILED DESCRIPTION Definitions

“Braid” refers to a structure made of interwoven strands.

“Catheter” is used in its generic sense and refers to any surgicalinstrument used to deliver a surgical device or chemical substance to aparticular location in to the interior of a patient's body.

“Coil” refers to a structure made of a series of rings or spirals.

“Distal Section” refers to a location on a retention device and coupledmedical device most distant from the operator.

“Elastomeric Polymeric Coating” refers to a polymeric coating based onsilicone or urethane that is able to repeatedly be stretched andcontracted without breaking or cracking.

“Longitudinal” refers to a lengthwise dimension.

“Loop” refers to a structure which may be open or closed and where openhas the free end covered to prevent trauma to the patient.

“Medical Device” refers to any device used for medical, veterinary ordental treatment requiring temporary or permanent placement.

“Platform” is used in its generic sense and refers to a first structureto which a retention device is mounted, where the first structure iscoupled to an underlying second structure.

“Port” refers to an opening or a thinning in a wall.

“Proximal Section” refers to a location on a retention device andcoupled medical device closest to the operator and sufficiently inwardto allow the retention device to deploy subcutaneously.

“PTFE” refers to polytetrafluoroethylene.

“Subcutaneous” refers to the anatomical area between the skin and dermallayers and underlying muscle tissue.

“Vessel” refers to any anatomical structure that connects organs withina body or outside the body. Examples include but are not limited toarteries, veins, bile duct, ureter, urethra, esophagus or other bodyconduits.

NOMENCLATURE

-   -   10 Retention Device    -   12 Catheter    -   14 Anchor Sleeve    -   14 a Chamber    -   14 b Floor of Anchor Sleeve    -   16 Introducer Sheath    -   16 a Second Lumen    -   18 Anchor Mechanism    -   18 a Tine    -   18 b Control Rod    -   20 Port    -   22 Membrane    -   24 Braid    -   26 Hemostasis Valve    -   28 Eyelet    -   29 Lock Spring    -   32 Recess    -   34 Key    -   36 Liner    -   40 Handle    -   100 Retention Device    -   112 Catheter    -   114 Anchor Sleeve    -   114 a Chamber    -   118 Anchor Mechanism    -   118 a Tine    -   118 b Control Rod    -   120 Port    -   128 Eyelet    -   129 Lock Spring    -   130 Weld    -   218 Anchor mechanism    -   218 a Tine    -   218 b Control Rod    -   228 Eyelet    -   229 Lock Spring    -   230 Weld    -   400 Retention Device    -   412 Catheter    -   414 Anchor Sleeve    -   414 a Chamber    -   418 Anchor Mechanism    -   418 a Tine    -   418 b Control Rod    -   420 Port    -   428 Eyelet    -   429 Lock Spring    -   432 Recess    -   440 Handle    -   500 Retention Device    -   514 Anchor Sleeve    -   514 a Chamber    -   518 Anchor Mechanism    -   518 a Tine    -   518 b Inner End    -   520 Port    -   521 Membrane    -   522 Spring    -   524 Reinforcing Braid    -   534 Key    -   535 Handle    -   536 Key Aperture    -   538 Locking Stop    -   540 Shaft    -   542 Locking Recess    -   600 Retention Device    -   614 Anchor Sleeve    -   614 a Chamber    -   618 Anchor Mechanism    -   618 a Tine    -   618 b Inner End    -   620 Port    -   621 Membrane    -   622 Spring (Attached)    -   634 Key    -   636 Key Aperture    -   638 Liner    -   700 Retention Device    -   714 Anchor Sleeve    -   714 a Chamber    -   718 Anchor Mechanism    -   718 a Tine    -   718 b Inner End    -   720 Port    -   721 Membrane    -   722 Spring (Integrally Attached to Anchor Mechanism)    -   734 Key    -   736 Key Aperture    -   800 Retention Device    -   814 Anchor Sleeve    -   814 a Chamber    -   818 Anchor Mechanism    -   818 a Loop    -   818 b Inner End    -   820 Port    -   821 Membrane    -   822 Spring    -   834 Key    -   836 Key Aperture    -   900 Retention Device    -   910 Braid    -   912 Inner Sheath    -   913 Lumen    -   914 Outer Sheath    -   915 Sliding End    -   916 Locking Tab    -   918 Coating    -   920 Widest Circumference    -   1000 Retention Device    -   1010 Braid    -   1012 Inner Sheath    -   1013 Lumen    -   1014 Outer Sheath    -   1015 Sliding End    -   1016 Locking Tab    -   1020 Widest Circumference    -   1100 Retention Device    -   1110 Braid    -   1112 Inner Sheath    -   1114 Outer Sheath    -   1115 Sliding End    -   1116 Locking Tab    -   1120 Widest Circumference    -   1200 Retention Device    -   1210 Braid    -   1212 Inner Sheath    -   1214 Outer Sheath    -   1215 Sliding End    -   1216 Locking Tab    -   1220 Widest Circumference    -   1300 Retention Device    -   1314 Anchor Sleeve    -   1314 a Chamber    -   1318 Anchor Mechanism    -   1318 a Tine    -   1320 Port    -   1321 Membrane    -   1334 Key    -   1336 Key Aperture    -   1400 Retention Device    -   1410 Sheath    -   1412 Restraining Band    -   1414 Control Actuator    -   1416 Neck    -   1418 Anchor Mechanism    -   1418 a Tine    -   1419 Control Member    -   1420 Actuator    -   1422 Spring    -   1500 Retention Device    -   1512 Inner Sheath    -   1514 Outer Sheath    -   1516 Neck    -   1518 Anchor Mechanism    -   1518 a Tine    -   S Skin    -   V Vessel

Construction

As shown in FIG. 1, the present invention comprises a retention device10 which is useful for securing catheters 12 and other medical devicesbeneath the skin S of a patient. As shown in FIGS. 1 and 2, theinvention comprises an anchor sleeve 14 which is integrally attached toan introducer sheath 16 by such means as co-injection molding orco-extrusion. Additional methods of attachment between the anchor sleeve14 and introducer sheath 16, including but not limited to gluing,ultrasonic welding, mechanical fasteners, heat shrinkable tubing orthermal melting are also contemplated by and therefore within the scopeof the invention. As shown in FIGS. 2 and 2 a, the anchor sleeve 14defines a chamber 14 a and the introducer sheath 16 defines a lumen 16a. The chamber 14 a further defines a floor 14 b towards the distal end(unnumbered) of the anchoring sleeve 14 which sealably houses the anchormechanism 18, 118, 218. The interior of the chamber 14 a may be linedwith PTFE (not shown) to facilitate movement of the anchor mechanism 18,118, 218 within it. A sealed chamber 14 a is advantageous as it resistsand minimizes the flow of blood and other bodily fluids into and out ofthe retention device 10 during the period of anchoring andcatheterization, which could cause infection due to the potentiallyrelatively long period of placement of the retention device 10 withinthe patient's body. An additional advantage to a sealed chamber 14 a isthat tissue in-growth is resisted, which could otherwise potentiallyinterfere with and cause seizure of the anchor mechanism 18, 118, 218thereby making normal removal impossible. A hemostasis valve 26, whichis well known in the art, is attached to the proximal end (unnumbered)and collinear with the introducer sheath 16 to prevent the leakage ofblood and other bodily fluids from the device 10 during use. The innerdiameter of the lumen 16 a is sized to be able to accommodate the outerdiameter of a catheter 12. Thus, when the device 10 is inserted into apatient, a catheter 12 or other medical device (not shown) will extendfirst through the hemostasis valve 26, then through the lumen 16 a andfinally into the desired vessel V, organ (not shown) or body cavity (notshown).

A number of ports 20 in equal number to the number of tines 18 a, 118 a,218 a are formed through the anchor sleeve 14 to permit deployment ofthe tines 18 a, 118 a, 218 a during treatment. In a preferredembodiment, a thin membrane 22 of a suitable plastic material such aspolyurethane, silicone or latex covers the ports 20. The membrane 22serves to seal the retention device 10 prior to deployment of the tines18 a, 118 a, 218 a. As explained in greater detail below, duringdeployment the tines 18 a, 118 a, 218 a will puncture the membrane 22.

As best shown in FIGS. 3-5, another embodiment of the retention device100 comprises an anchoring sleeve 114 integrally attached to a catheter112 (and associated structures such as a hub/body) or other medicaldevices by such means as co-injection molding or co-extrusion. Theanchoring sleeve 114 further defines a chamber 114 a, which may becoated with PTFE (not shown) to facilitate movement of the anchormechanism 18, 118, 218. In additional embodiments the anchoring sleeve114 can be attached to the catheter 112 by any other suitable means,such as by gluing, ultrasonic welding, mechanical fasteners or thermalmelting means. The chamber 114 a further defines a floor 114 b towardsthe distal end (unnumbered) of the anchor sleeve 114 and also sealablyaccommodates the anchor mechanism 18, 118, 218 which, as explained indetail below, extends to form lock spring 29, 129. This resists andminimizes the inflow of blood and other bodily fluids into the retentiondevice 100 during the period of anchoring and catheterization, whichcould cause infection due to the potentially relatively long period ofplacement of the retention device 100 within the patient's body. Anadditional advantage to a sealed chamber is that tissue in-growth isresisted, which could otherwise potentially interfere with and causeseizure of the anchor mechanism 18, 118, 218 thereby making normalremoval impossible. In a manner similar to that shown in FIG. 1 withregard to the embodiment of the retention device 10, this embodiment ofthe retention device 100 is likewise introduced (not shown) through apatient's skin S and into a vessel V or other anatomical site prior todeployment of the tines 18 a, 118 a, 218 a to secure the retentiondevice 100 to the patient's body.

A number of ports 120 in equal numbers to the numbers of tines 18 a, 118a, 218 a are formed through a side wall (unnumbered) of the anchorsleeve 114 to permit deployment of the tines 18 a, 118 a, 218 a duringtreatment. In a preferred embodiment, a thin membrane 22 of a suitablelow durometer plastic material such as polyurethane, silicone and latexcovers the ports 120. The membrane 22 serves to seal the retentiondevice 10 prior to deployment of the tines 18 a, 118 a, 218 a. Asexplained in greater detail below, during deployment, the tines 18 a,118 a, 218 a will puncture the membrane 22.

Suitable materials for the anchor sleeve 14, 114 and introducer sheath16 include various plastic materials including polyurethane, polyimide,PBAX, polyethylene or PTFE reinforced by stainless steel, titanium ornitinol braid 24 or coil (not shown). Carbon fiber materials comprise analternative braiding material. Titanium, nitinol or stainless steeltubing are alternative reinforcement materials. The reinforcing braid 24or alternative reinforcement is necessary to add additional strength toconstrain the tines 18 a, 118 a, 218 a from premature deployment throughthe anchor sleeve. In an alternative embodiment, as shown in FIGS. 2 aand 2 b, the anchor sleeve 14, 114 is reinforced by a liner 36 made of astronger material such as ultra high density polyethylene, high densitypolyethylene or nylon and derivatives or combinations of the above. Theliner 36 can be a separately molded inserted piece or be incorporatedinto the anchor sleeve 14, 114 during the molding process. It is alsocontemplated to insert a liner 36 impregnated (not shown) with a braid24 or coil (not shown).

The outer surfaces (unnumbered) of the retention device 10, 100 can becoated (not shown) with a variety of commercially available compounds.These include but are not limited to antithrombogenic, antibacterial, oranti-inflammatory compounds to reduce tissue ingrowth, or preventinfection due to the presence of the retention device 10, 100 in thepatient for extended periods. These compounds are also useful inimproving the biocompatibility of the retention device 10, 100 andinclude but are not limited to heparin complex solutions, benzalkoniumheparinate, triodoecylmethylammonium heparinate, chlorhexidine-silversulfadiazine, myococycline and rifampin.

Upon introducing a catheter, sheath introducer, or other medical deviceincorporating the retention device 10 through a patient's skin S andinto a vessel V such as an artery (not specifically shown), vein (notspecifically shown) or other duct (not specifically shown), vessel ororgan (not specifically shown), the tines 18 a, 118 a, 218 a of theanchor mechanism 18, 118, 218 are deployed through the ports 20, 120thereby securing the catheter 12, 112, introducer sheath 16 or otherdevice (not shown) to the patient's body subcutaneously. The mechanismfacilitating tine 18 a, 118 a, 218 a deployment is more fully explainedbelow.

An embodiment of an anchor mechanism 18 is best shown in FIGS. 6 a, 6 band 7. This embodiment of the anchor mechanism 18 comprises at least asingle tine 18 a and in a preferred embodiment has two tines 18 a butmay also have additional numbers of tines 18 a such as three (notshown), four (not shown), five (not shown), six (not shown) or evengreater numbers of tines 18 a (not shown). The tips (unnumbered) of thetines 18 a may be sharp (not shown), dull as shown in FIG. 2 b orrounded as shown in FIGS. 6 a and 8-9. A control rod 18 b is integrallyattached to the tines 18 a. At the proximal end (unnumbered) of thecontrol rod 18 b is an eyelet 28 formed integrally with the control rod18 b, which serves either as a convenient grip or as the connector foran attached handle 40. The control rod 18 b extends proximally and istrained to bend over to form an eyelet 28. The control rod 18 b andeyelet 28 then reverse direction to a distal direction to form the lockspring 29 which is raised above the length of the control rod 18.Together the tines 18 a and control rod 18 b comprise the anchormechanism 18. As will be explained in greater detail below, deploymentof the tines 18 a through the ports 20, 120 in the anchor sleeve 14, 114secures the retention device 10, 100 within the body of the patient fora period sufficient to complete the desired treatment. Moving thecontrol rod 18 b in a proximal direction thus simultaneously moves thefixedly attached tines 18 a in a proximal direction, eventually causingthe tines 18 a to extend through the ports 20, 120 followingintroduction of the retention device 10, 100 within a patient. As shownin FIG. 6 a the tines 18 a may have a consistent width or, in analternative embodiment, as shown in FIG. 6 b, the tines 18 a may betapered.

In one embodiment, making the anchor mechanism 18 involves acquiringnitinol tubing having a length sufficient to allow a control rod 18 blong enough to extend through the proximal end of the anchor sleeve 14,114 so as to be able to connect control rod 18 b to the handle 40. Thetubing preferably has a wall thickness between 0.005 to 0.030 inches,however, lesser and greater wall thicknesses are also contemplated byand therefore within the scope of the invention. Portions of the lengthof tubing are then cut away by means of well known techniques such asEDM (electron discharge machining), laser cutting, traditional machiningor water jet. The remaining portions of the tubing comprise the anchormechanism 18, and its integrally attached tines 18 a, control rod 18 b.As explained in detail above, eyelet 28 and lock spring 29 are formedfollowing cutting of the nitinol tubing. Using this manufacturingtechnique, anchor mechanisms 18 having wide variations are possible. Itis also contemplated by the invention to make an integral anchormechanism 18 from a flat sheet of nitinol. In this embodiment, at leastthe tines 18 a and lock spring 29 are processed so as to have a trainedshape when in an unrestrained state somewhere below human bodytemperature of 37 degrees C. The trained shape of the tines 18 a can bea partial arc as shown in FIGS. 2 b, 6 a, 6 b 7, 8, 9, 11, 13 and 15, asemi circular arc (not shown) or even a complete arc (not shown). Itshould be mentioned that the anchor mechanism could also be made fromstainless steel or other alloys such as elgiloy, MP35N, incoloy, othersuperalloys or plastically deformable materials.

Two alternative embodiments of the anchor mechanism 118, 218 are shownin FIGS. 8 and 9. These anchor mechanisms 118, 218 differ from theanchor mechanism 18 shown in FIGS. 6 a, 6 b and 7 in that they areconstructed from pieces of nitinol ribbon wire comprising tines 118 a,218 a and control rod 118 b, 218 b having welds 130, 230 at a distal end(unnumbered) of the anchor mechanism 118, 218. In a preferred embodimentthe welds 130, 230 are accomplished by a laser, however, other weldingtechnologies such as resistance welding and friction welding could alsobe used. Additionally, hypotubing could used to attach the tines 118 a,218 a to the control rod 118 b, 218 b. The anchor mechanism 118 shown inFIG. 8 has two tines 118 a welded to the control rod 118 b; the anchormechanism 218 shown in FIG. 9 has only a single tine 218 a welded to thecontrol rod 218 b. Control rod 118 b, 218 b extends proximally and istrained to bend over to form an eyelet 128, 228. The wire forming thecontrol rod 118 b, 218 b and eyelet 128, 228 then reverse direction to adistal direction to form the lock spring 129, 229 which is raised abovethe length of the control rod 118 b, 218 b. Anchor mechanisms 118, 218function in a similar manner as the anchor mechanism 18 described above.FIG. 12 shows an additional embodiment of the anchor mechanism 218loaded into the retention device 10 prior to deployment of the tine 218a. FIG. 13 shows this embodiment of the anchor mechanism 218 loaded intothe first embodiment of the retention device 10 following deployment ofthe tine 218 a.

As shown in FIGS. 10-11 and 14-15, the retention device 10, 100 isprovided with a lock mechanism (unnumbered) comprising a lock spring 29and a recess 32. In the undeployed configuration, the lock spring 29 iscompressed against the inner dimension (unnumbered) of the chamber 14 a,114 a. This is due to the normal, trained shape of the lock spring 29being greater than the inner dimension (unnumbered) of the chamber 14 a,114 a. When the control rod 18 b, 118 b is distally moved by thephysician, as discussed above, the tines 18 a, 118 a, 218 a will deploythrough the ports 20, 120. Upon reaching a predetermined proximaldistance, when the tines 18 a, 118 a, 218 a are fully deployed, the lockspring 29 will reach the internal recess 32 of the chamber 29 and moveoutward, to fit into the recess 32, thus locking the retention device10, 100 in the deployed position and securing it in place in thepatient. To remove the retention device 10, 100 a key 34 is providedwhich permits the physician to externally depress the lock spring 29,thus making distal movement of the control rod 18 b, 118 b possible,allowing eventual removal of the retention device 10, 100 from thepatient. It is also contemplated and therefore within the scope of theinvention to have a series of recesses (not shown) along the length ofthe inner dimension of the chamber 14 a, 114 a allowing the physician adegree of control over the amount of tine 18 a, 118 a, 218 a that isdeployed.

FIG. 16 shows an additional embodiment of the retention device 400 wherethe anchor mechanism 418 surrounds the lumen 412 of the catheter 412 towhich an anchor sleeve 414 is attached. The anchor sleeve 414 defines achamber 414 a into which the anchor mechanism 418 is loaded prior todeployment. A control rod 418 b is distally attached to a plurality oftines 418 a. When the control rod 418 b is moved proximally the tines418 a will extend through ports 420 that correspond to the individualtines 418 a as more fully discussed above. The retention device 400 isfitted with a lock spring 429 which fits into a recess 432 followingdeployment of the tines 418 a. An eyelet 428 is formed at the proximalend (unnumbered) of the control rod 418 b. A handle 440 is preferablyattached around the eyelet 428 to facilitate deployment of the tines 418a following insertion into the patient. FIG. 17 shows a cross sectionalview of the embodiment of the retention device 400 following deploymentof the tines 418 a.

FIG. 18 shows an embodiment of the retention device 500 in theundeployed configuration, with the tine(s) 518 a retracted inside thechamber 514 a. FIG. 19 shows the anchoring device 500 in the deployedconfiguration, following deployment of the tine(s) 518 a through theport(s) 520. In this embodiment 500, the anchor mechanism 518 is loadedinto an anchor sleeve 514, defining a chamber 514 a which serves tohouse the anchor mechanism 518 and spring 522. It should be mentionedthat additional biasing means are contemplated by and therefore withinthe scope of the invention. Additional biasing means include hydraulicand pneumatic cylinders (not shown) and various kinds of plasticmaterials (not shown) having spring-like characteristics. A number ofports 520 in equal number to the number of tines 518 a are formedthrough the anchor sleeve 514 to permit deployment of the tines 518 aduring deployment during treatment. In a preferred embodiment, a thinmembrane 521 of a suitable plastic material such as polyurethane,silicone or latex covers the port(s) 520. The membrane 521 serves toseal the retention device 500 prior to deployment of the tine(s) 518 a.A sealed chamber 514 a is advantageous as it resists and minimizes theflow of blood and other bodily fluids into and out of the retentiondevice 500 during the treatment period which could cause infection dueto the potentially long period of placement of the retention device 500within the patient's body. An additional advantage to a sealed chamber514 a is that tissue in-growth is resisted, which could otherwisepotentially interfere with or cause seizure of the anchor mechanism 518thereby making normal removal difficult if not impossible. The anchormechanism 518 is formed in a generally “U” shaped configuration and hasat least a single tine 518 a which is terminated by a free end(unnumbered) and an inner end 518 b, which is opposite the free end(unnumbered). In the embodiment of the anchoring device 500 as shown inFIGS. 18-19 a, the anchor mechanism 518 is a unitary, integratedelement, however, it is also contemplated to have the anchor mechanism518 be made of attached, separately manufactured pieces (not shown). Anunattached spring 522 is placed into the chamber 514 a proximate theinner end 518 b to provide a bias to the anchor mechanism 518 such thatit will default in a manner where the tine(s) 518 a extend or deployfrom the anchor sleeve 514 through the port(s) 520. The anchor mechanism518 is preferably made from nitinol which has been processed to exhibitsuperelasticity at a temperature below human body temperature. Thenature, processing and advantages of superelasticity are discussed indetail below. Additional materials for building the anchor mechanism 518include but are not limited to stainless steel, elgiloy, MP35N, incoloy,other superalloys or plastically deformable materials.

A key 534 is provided which is shaped and sized to fit into the keyaperture 536 whereby when the key 534 is inserted into the key aperture536 the tine(s) 518 a is/are replaced inside the anchor sleeve 514. FIG.18 b shows in greater detail the key 534 inserted into the anchor sleeve514. The key itself comprises a handle 535 which is attached to alocking stop 538 which extends from the handle 535. Extending from thelocking stop 538 is a shaft 540 having a diameter (unnumbered) sized tofit within the key aperture 536 and a length (unnumbered) sufficient tocontact the anchor mechanism 518. The anchor sleeve 514 further definesa locking recess 542 which is dimensioned to have a concave interiorprofile that snugly mates with the outer contours (unnumbered) of thelocking stop 538 on the key 534, providing a snap lock fit thatmaintains the key 534 and retaining device 500 in the undeployedconfiguration as shown in FIG. 18 b as long as it is inserted. Either orboth the anchor sleeve 514 or the locking stop 538 are made frompolyurethane, polyimide, PBAX, polyethylene or PTFE which, because oftheir partially elastic nature, allows the locking stop 538 and lockingrecess to be used as a snap lock. FIG. 19 b shows the key 534 removedfrom the anchor sleeve 514 following deployment of the anchor mechanism518. FIGS. 18 b and 19 b are specifically directed to the details of thekey 534 and associated structures as applying to the embodiment of theretention device 500 shown in FIGS. 18-19 b. It should further bementioned that the other embodiments of the retention device 600, 700,800, 1300 utilizing an anchor sleeve 614, 714, 814, 1314 describedherein, while not showing the details shown in FIGS. 18 b and 19 b, havesimilar locking key structures (not shown) incorporated that allow thephysician to control deployment of the anchor mechanism 618, 718, 818,1318.

Suitable materials for the anchor sleeve 514 include various plasticmaterials including polyurethane, polyimide, PBAX, polyethylene or PTFEreinforced by stainless steel, titanium or nitinol braid 524 or coil(not shown). Carbon fiber materials comprise an alternative braidingmaterial. The reinforcing braid 524 is desirable to add additional wallstrength to constrain the tines 518 a from uncontrolled deploymentthrough the anchor sleeve 514. In an alternative embodiment, as shown inFIG. 20 b, the anchor sleeve 614 is reinforced by a liner 638 made of astronger material such as ultra high density polyethylene, high densitypolyethylene or nylon and derivatives or combinations of the above. Theliner 638 can be a separately molded inserted piece or be incorporatedinto the anchor sleeve 614 during the molding process. It is alsocontemplated to insert a liner (not shown) impregnated (not shown) witha braid (not shown) or coil (not shown). While the liner 638 is shownillustrating the embodiment of the retention device 600 as shown inFIGS. 20-20 b, the concept of a liner 638 is equally applicable to theother embodiments 500, 600, 700, 800, 1300 discussed herein.

The outer surfaces (unnumbered) of the retention device 500 can becoated (not shown) with a variety of commercially available compounds.These include but are not limited to antithrombogenic, antibacterial, oranti-inflammatory compounds to reduce tissue ingrowth, or preventinfection due to the presence of the retention device 500 in the patientfor extended periods. These compounds are also useful in improving thebiocompatibility of the retention device 500 and include but are notlimited to heparin complex solutions, benzalkonium heparinate,triiodoecylmethylammonium heparinate, chlorhexidine-silver sulfadiazine,myococycline and rifampin.

Yet another embodiment of the retention device 600 is shown in FIGS.20-20 b. This embodiment 600 is similar to the embodiment of theretention device 500 shown in FIGS. 18 and 19 and differs mainly inhaving the spring 622 attached proximate the inner end 618 b of theanchor mechanism 618 by welding, gluing, crimping, fasteners or anyother secure and permanent method. The retention device 600 shown inFIG. 20 has an anchor sleeve 614 defining a chamber 614 a, which servesto house the anchor mechanism 618 and spring 622. The anchor mechanism618 is formed in a generally “U” shaped configuration and has at least asingle tine 618 a which terminates in a free end (unnumbered) and aninner end 618 b, which is opposite the free end (unnumbered). In theembodiment of the anchoring device 600 as shown, the anchor mechanism618 is a unitary, integrated element, however, it is also contemplatedto have the anchor mechanism 618 be made of attached, separatelymanufactured pieces (not shown). A key 634 is provided which is shapedand sized to fit into a key aperture 636 whereby when the key 634 ispushed into the key aperture 636 the tine(s) 618 a is/are replacedinside the chamber 614 a.

Suitable materials for the anchor sleeve 614 include various plasticmaterials including polyurethane, polyimide, PBAX, polyethylene or PTFEreinforced by stainless steel, titanium or nitinol braid (not shown) orcoil (not shown). Carbon fiber materials comprise an alternativebraiding material. The reinforcing braid (not shown) is desirable to addadditional strength to constrain the tines 618 a from prematuredeployment through the anchor sleeve 614. In an alternative embodiment,as shown in FIG. 20 b, the anchor sleeve 614 is reinforced by a liner638 made of a stronger material such as ultra high density polyethylene,high density polyethylene or nylon and derivatives or combinations ofthe above. The liner 638 can be a separately molded inserted piece or beincorporated into the anchor sleeve 614 during the molding process. Itis also contemplated to insert a liner 638 impregnated (not shown) witha braid or coil (not shown).

The outer surfaces (unnumbered) of the retention device 600 can becoated (not shown) with a variety of commercially available compounds.These include but are not limited to antithrombogenic, antibacterial, oranti-inflammatory compounds to reduce tissue ingrowth, or preventinfection due to the presence of the retention device 600 in the patientfor extended periods. These compounds are also useful in improving thebiocompatibility of the retention device 600 and include but are notlimited to heparin complex solutions, benzalkonium heparinate,triodoecylmethylammonium heparinate, chlorhexidine-silver sulfadiazine,myococycline and rifampin.

Still another embodiment of the retention device 700 is shown in FIG.21. This embodiment 700 is similar to the embodiments shown in FIGS.18-20 b and differs mainly in having the spring 722 integrally attachedproximate the inner end 718 b. The anchoring device 700 shown in FIG. 21has an anchor sleeve 714 defining a chamber 714 a, which serves to housethe anchor mechanism 718 and integrally attached spring 722. A number ofports 720 in equal number to the number of tines 718 a are formedthrough the anchor sleeve 714 to permit deployment of the tines 718 aduring deployment during treatment. In a preferred embodiment, a thinmembrane 721 of a suitable plastic material such as polyurethane,silicone or latex covers the port(s) 720. The membrane 721 serves toseal the retention device 700 prior to deployment of the tine(s) 718 a.A sealed chamber 714 a is advantageous as it resists and minimizes theflow of blood and other bodily fluids into and out of the retentiondevice 700 during the treatment period which could cause infection dueto the potentially long period of placement of the retention device 700within the patient's body. An additional advantage to a sealed chamber714 a is that tissue in-growth is resisted, which could otherwisepotentially interfere with or cause seizure of the anchor mechanism 718thereby making normal removal difficult if not impossible. The anchormechanism 718 is formed in a generally “U” shaped configuration and hasat least a single tine 718 a which is terminated by a free end and aninner end 718 b, which is opposite the free end. In the embodiment ofthe anchoring device 700 as shown, the anchor mechanism 718 is aunitary, integrated element, however, it is also contemplated to havethe anchor mechanism 718 be made of attached, separately manufacturedpieces (not shown). An unattached spring 722 is placed into the anchorsleeve 714 proximate the inner end 718 b to provide a bias to the anchormechanism 718 such that it will default in a manner where the tine(s)718 a extend or deploy from the anchor sleeve 714 through the port(s)720. A key 734 is provided which is shaped and sized to fit into a keyaperture 736 whereby when the key 734 is pushed into the key aperture736 the tine(s) 718 a is/are replaced inside the anchor sleeve 714.

Suitable materials for the anchor sleeve 714 include various plasticmaterials including polyurethane, polyimide, PBAX, polyethylene or PTFEreinforced by stainless steel, titanium or nitinol braid or coil (notshown). Carbon fiber materials comprise an alternative braidingmaterial. The reinforcing braid (not shown) is desirable to addadditional wall strength to constrain the tines 718 a from prematuredeployment through the anchor sleeve 714. In an alternative embodiment(not shown) the anchor sleeve 714 is reinforced by a liner (not shown)made of a stronger material such as ultra high density polyethylene,high density polyethylene or nylon and derivatives or combinations ofthe above. The liner (not shown) can be a separately molded insertedpiece or be incorporated into the anchor sleeve 714 during the moldingprocess. It is also contemplated to insert a liner (not shown)impregnated (not shown) with a braid or coil (not shown).

The outer surfaces (unnumbered) of the retention device 700 can becoated (not shown) with a variety of commercially available compounds.These include but are not limited to antithrombogenic, antibacterial, oranti-inflammatory compounds to reduce tissue ingrowth, or preventinfection due to the presence of the retention device 700 in the patientfor extended periods. These compounds are also useful in improving thebiocompatibility of the retention device 700 and include but are notlimited to heparin complex solutions, benzalkonium heparinate,triodoecylmethylammonium heparinate, chlorhexidine-silver sulfadiazine,myococycline and rifampin.

FIG. 22 shows an alternative embodiment of the retention device 800 inthe deployed configuration. FIG. 23 shows the retention device 800 shownin FIG. 22 in the undeployed configuration. The embodiment of theretention device 800 is similar to the embodiments 500, 600, 700 shownin FIGS. 18-21 a with the difference being that the anchor mechanism518, 618, 718 having tines 518 a, 618 a, 718 a is replaced by atraumaticloops 818 a. The loops 818 a are, in essence, longer tines that havebeen processed to bend back around themselves to form a tight “U”, thefree end (unnumbered) of which remains inside the chamber 814 a at alltimes. The advantage of this configuration is that rounded loop(s) 818 aare less likely to puncture or lacerate contacted tissue during thetreatment period when the patient's physical movement might cause aslight disruption of the retention device 800 and coupled medicaldevice. The anchor mechanism 818 is loaded into an anchor sleeve 814defining a chamber 814 a which serves to house the anchor mechanism 818and spring 822 and is further provided with a number of ports 820 equalto the number of loops 818 a which are attached to the anchor mechanism818. The ports 820 are formed through the anchor sleeve 814 to permitdeployment of the loops 818 a during deployment during treatment. In apreferred embodiment, a thin membrane 821 of a suitable plastic materialsuch as polyurethane, silicone or latex covers the port(s) 820. Themembrane 821 serves to seal the retention device 800 prior to thedeployment of the loop(s) 818 a. A sealed chamber 814 a is advantageousas it resists and minimizes the flow of blood and other bodily fluidsinto and out of the retention device 800 during the treatment periodwhich could cause infection due to the potentially long period ofplacement of the retention device 800 within the patient's body. Anadditional advantage to a sealed chamber 814 a is that tissue in-growthis resisted, which could otherwise potentially interfere with or causeseizure of the anchor mechanism 818 thereby making normal removaldifficult if not impossible.

In the embodiment of the anchoring device 800 as shown in FIGS. 22-23,the anchor mechanism 818 is a unitary, integrated element, however, itis also contemplated to have the anchor mechanism 818 be made ofattached, separately manufactured pieces (not shown). An spring 822 isplaced into the anchor sleeve 814 proximate the inner end 818 b toprovide a bias to the anchor mechanism 818 such that it will default ina manner where the loop(s) 818 a extend or deploy from the anchor sleeve814 through the port(s) 820. The anchor mechanism 818 is preferably madefrom nitinol which has been processed to exhibit superelasticity at atemperature below human body temperature. The nature, processing andadvantages of superelasticity are discussed in detail below. Additionalmaterials for building the anchor mechanism 818 include but are notlimited to stainless steel, elgiloy, MP35N, incoloy or othersuperalloys. A key 834 is provided which is shaped and sized to fit intoa key aperture 836 whereby when the key 834 is pushed into the anchorsleeve 814 the tine(s) 818 a is/are replaced inside the anchor sleeve814.

Suitable materials for the anchor sleeve 814 include various plasticmaterials including polyurethane, polyimide, PBAX, polyethylene or PTFEreinforced by stainless steel, titanium or nitinol braid (not shown) orcoil (not shown). Carbon fiber materials comprise an alternativebraiding material. The reinforcing braid (not shown) is desirable to addadditional strength to constrain the loop(s) 818 a from prematuredeployment through the anchor sleeve 814. In an alternative embodiment,as shown in FIG. 18 b, the anchor sleeve 814 is reinforced by a liner(not shown) made of a stronger material such as ultra high densitypolyethylene, high density polyethylene or nylon and derivatives orcombinations of the above. The liner (not shown) can be a separatelymolded inserted piece or be incorporated into the anchor sleeve 814during the molding process. It is also contemplated to insert a liner(not shown) impregnated (not shown) with a braid (not shown) or coil(not shown).

The outer surfaces (unnumbered) of the retention device 800 can becoated (not shown) with a variety of commercially available compounds.These include but are not limited to antithrombogenic, antibacterial, oranti-inflammatory compounds to reduce tissue ingrowth, or preventinfection due to the presence of the retention device 800 in the patientfor extended periods. These compounds are also useful in improving thebiocompatibility of the retention device 800 and include but are notlimited to heparin complex solutions, benzalkonium heparinate,triodoecylmethylammonium heparinate, chlorhexidine-silver sulfadiazine,myococycline and rifampin.

FIGS. 24 and 25 show another embodiment of the retention device 900having a length of braid 910 attached at one end to an inner sheath 912and at the other end to an outer sheath 914. As best shown in FIG. 25 a,the inner sheath 912 defines a lumen 913 which allows fluidcommunication to occur between both ends of the inner sheath 912. In oneembodiment, the inner sheath 912 may actually be a catheter (not shown)or other medical device used to provide communication between the insideof a patient's body and the outside. In other embodiments, the innersheath 912 is a separate structure coupled to a catheter or othermedical device. The outer sheath 914 defines an inner dimension(unnumbered) and the inner sheath 912 defines an outer dimension(unnumbered) and is sized to allow the outer sheath 914 to slidablyengage the outer diameter of the inner sheath 912. In one embodiment asshown in FIGS. 24 and 25, the braid 910 is attached at one end to theinner sheath 912 which is fixed and at the other end to a sliding end915 of the outer sheath 914, which slidably engages the inner sheath 912and causes the braid 910 to deploy as discussed below. In anotherembodiment (not shown), the outer sheath 914 is fixed in position andthe inner sheath 912 slidably moves to cause the braid 910 to deploy.

The nature of the attached braid 910 is such that it defines alongitudinal dimension (unnumbered) and a diameter (unnumbered) whichare in inverse relationship with each other, i.e., as the longitudinaldimension (unnumbered) increases, the diameter (unnumbered)simultaneously decreases. Depending on the degree of decreasing thelongitudinal dimension (unnumbered), a great variety of combinations oflongitudinal dimensions and diameters is possible. The braid 910 ispreferably woven from a plurality of strands (unnumbered) of nitinolalloy that is processed to exhibit superelasticity at somewhere belowhuman body temperature. In an alternative embodiment, the braid 910could also be made from various stainless steel alloys, polymericmaterials or composite materials. It should be mentioned that thenitinol braid 910 could be processed (i.e., mechanically and heattreated) to be in either the shortened configuration as shown in FIG. 24in an unrestrained state at somewhere below human body temperature or inthe elongated configuration as shown in FIG. 25 at somewhere below humanbody temperature.

In a preferred embodiment, as shown FIG. 25 a, the braid 910 is coatedwith an elastomeric coating 918 such as a medical grade silicone orurethane. The coating 918 completely encases the braid 910 closing thespaces (unnumbered) between individual strands (unnumbered)(i.e., formsa web) and is able to expand and/or contract as deployment occurs due toits elastomeric nature. Coating 918 is desirable because it preventsingrowth from occurring into the braid 910 during the treatment period,which may be relatively lengthy. The invention also contemplates coatingthe braid 910 in a manner wherein the individual strands (unnumbered)are coated, but the spaces between the strands are open (not shown).

To deploy the retention device 900 following introduction into apatient, the braid 910 is moved from the elongated configuration asshown in FIG. 25 into the shortened configuration as shown in FIG. 24 bysliding the outer sheath 914 toward the point of braid 910 attachment onthe inner sheath 912. This causes the braid 910 to shorten and widen,eventually defining a widest circumference 920 thus subcutaneouslyretaining the coupled medical device (not shown) within the patient forthe duration of treatment. A locking tab 916 is formed into the outersheath 914 to maintain the retention device 900 in the deployedconfiguration for the duration of the treatment period.

As shown in FIGS. 28, 29 and 29 a, the invention also contemplates anadditional embodiment of the retention device 1000 having the braid 1010in an uncoated version. In other aspects, this embodiment of theinvention is similar to the embodiment shown in FIGS. 24, 25 and 25 a.

In the embodiments of the retention device 900, 1000 it can be seen thatthe braid 910, 1010 when in the shortened configuration as shown inFIGS. 24 and 28 is in a symmetrical configuration. In thisconfiguration, both sides (unnumbered) of the shortened braid 910, 1010are approximately equal in shape and size and the widest circumference920, 1020 extends around the longitudinal axis (unnumbered) of the innersheath 912, 1012 at an approximate 90 degree angle. As shown in FIGS. 26and 27, in alternative embodiments 1100, 1200 the braid 1110, 1210 canalso be trained to be in an asymmetrical configuration when in theshortened state. FIG. 26 shows a braid 1110 which assumes aconfiguration where the widest circumference 1120 extends around thelongitudinal axis (unnumbered) of the inner sheath 1112 at anapproximate 45 degree/45 degree angle. FIG. 27 shows a braid 1210 whichassumes a configuration where the widest circumference 1220 extendsaround the longitudinal axis (unnumbered) of the inner sheath 1212 at anapproximate 60 degree/30 degree angle. The advantage of the asymmetricbraid configurations shown in FIGS. 26-27 is that the medical device(unnumbered) attached to the retention device 1100, 1200 extends fromthe patient at a more comfortable and stable angle. It is also possibleto achieve asymmetric shortened braid configurations by means ofasymmetrical braiding techniques.

Except for the asymmetrical configuration of the widest circumference1120, 1220 the embodiments of the retention device 1100, 1200 aresimilar in other aspects to the embodiments of the retention device 900,1000 discussed above.

FIGS. 30-31 show a cut away side view of a further embodiment of theinvention 1300. The embodiment 1300 is similar to the embodiments 500,600, 700, 800 shown in, respectively, FIGS. 18-23, with the differencebeing an anchor mechanism 1318 that is cut or machined from a length ofmetallic tubing. The metallic tubing can be cut by such well knownmethods as wire electrical discharge machining (EDM), mechanicalcutting, laser cutting, water jet or traditional machining. At least oneand preferably a plurality of tines 1318 a is formed by cutting orremoving metal along an axis parallel with the longitudinal axis of thetubing. In a preferred embodiment, the anchor mechanism 1318 is cut froma length of nitinol tubing and then at least the tine(s) 1318 a areprocessed as described below to program the nitinol to exhibitsuperelasticity at somewhere below human body temperature.

FIGS. 32-33 show a cut away side view of another embodiment of theinvention 1400. The retention device 1400 comprises a sheath 1410 whichdefines a length (unnumbered), a neck 1416 which is a section of thesheath 1410 having a lesser diameter and a groove 1414 whichaccommodates an actuator 1420. A retaining band 1412 surrounds the neck1416 and is fixedly attached to the neck 1416 at several points(unnumbered). An anchor mechanism 1418 is cut or machined as describedwithin and defines at least a single tine 1418 a. The anchor mechanism1418 as shown in FIGS. 32-33 at least partially surrounds and isexternally slidably mounted to the neck 1416. The anchor mechanism ispreferably made from a piece of nitinol tubing which has had sectionscut away to produce free ended tines 1418 a which can be trained orprocessed into possessing a superelastic, unrestrained, assumable shape,as discussed elsewhere. A spring 1422 is mounted to the sheath 1410 orneck 1416 and biases the anchor mechanism 1418 toward the deployedconfiguration as best shown in FIG. 33. An actuator 1420 is fitted intothe groove 1414 and maintains the retention device 1400 in theundeployed configuration as best shown in FIG. 32 by preventing theanchor mechanism 1418 from sliding in the biased direction until thedevice is introduced into the patient. The actuator 1420 is connected tothe anchor mechanism 1418 by a control member 1419. While in theundeployed configuration the tine(s) 1418 a are held against the neck1416 by the retaining band 1412. Because the retaining band 1412 isattached to the neck 1416 at several points, additional spaces(unnumbered) are defined through which the tine(s) 1418 a can escape asthe anchor mechanism 1418 slides in its biased direction, to assume thedeployed configuration.

FIGS. 34-35 show a cut away side view of an embodiment of the retentiondevice 1500. The retention device comprises an inner sheath 1512defining a length (unnumbered), a width (unnumbered) and a neck 1516,which is a section of the inner sheath 1512 having a lesser diameter. Ananchor mechanism 1518 defining at least a single tine 1518 a at leastpartially surrounds and is externally and fixedly attached to the neck1516. An outer sheath 1514 defines a length (unnumbered), a width(unnumbered) and a number of ports 1520 corresponding with the number oftines 1518 a and is sized to slidably fit over the inner sheath 1512. Tomaintain the retention device 1500 in the undeployed configuration, theouter sheath 1514 is slid into a position along the length of the innersheath 1512 to restrain the tine(s) 1518 a with the tip (unnumbered)proximate the corresponding port 1520. Following successful introductioninto the patient of the retention device 1500 and coupled medicaldevice, the outer sheath 1514 is slid in a direction as shown in FIG. 35allowing the tine(s) 1518 a to escape through the ports 1520 to assumetheir trained shape, thus subcutaneously deploying the retention device1500 for the duration of treatment. At the completion of treatment, theouter sheath 1514 is slid into the position shown in FIG. 34, againrestraining the tine(s) 1518 a allowing removal of the retention device1500 and coupled medical device from the patient.

FIG. 36 shows a side view of the embodiment of the retention device 500coupled with an introducer sheath 16 following successful introductioninto a patient and subcutaneous deployment of the tines 518 a. It isemphasized that this combination of coupled retention device 500 andmedical device is exemplary and in no way intended to be limiting. Thus,the other embodiments of the retention device 10, 100, 200, 400, 600,700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500 discussed herein couldalso be equally successfully coupled to a variety of other medicaldevices used for temporary but relatively long term placement.

All embodiments of the sutureless retention device 10, 100, 200, 400,500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500 can beconfigured to be separately attachable to any kind of medical device.Attachment means include but are not limited to injection molding,co-extrusion, press fit, adhesives, hook and loop fastener material,snaps, retaining rings, thermal melting techniques, sonic welding,crimping, heat shrink, mechanical fasteners, or an introducer sheath.

Making the embodiments of the anchor mechanism 18, 118, 218, 518, 618,718, 818 involves acquiring lengths of nitinol ribbon wire or sheet. Inthe embodiments shown in FIGS. 1-2, 6 a, 6 b, 7, 10, 10 a, 11, 15, 18-23the anchor mechanism 18, 518, 618, 718, 818 is made from a single pieceof nitinol ribbon wire or sheet. In the embodiments shown in FIGS. 8, 9,12, 13 and 14, separate pieces eventually becoming control rod 118 b andtines 118 a are then cut to appropriate lengths and attached at a distalend 130, 230 by means of laser welding. In an alternative embodiment,the tines 118 a, 218 a could also be attached to the control rod 118 b,218 b by soldering, gluing or mechanical bonding. It should also bementioned that anchor mechanisms 118, 218 could also be similarly madefrom round wire (not shown) and square wire (not shown). In theembodiment shown in FIGS. 16-17 and 30-31, the anchor mechanism 418,1318, 1418, 1518 is made from a length of nitinol tubing which is cut ormachined and heat treated as discussed below. Further, alternativematerials such as stainless steel or elgiloy could also be used.

As shown in FIG. 6 b, the tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a,718 a, 1318 a can be tapered toward the free end (unnumbered), however,it is not essential to have tapered tines. The advantage to thisconfiguration is that tapered tines 18 a, 118 a, 218 a, 418 a, 518 a,618 a, 718 a, 1318 a, 1418 a, 1518 a would have increased buckling atthe attached end (unnumbered) as well as improved trauma characteristicsat the free end (unnumbered). It is additionally contemplated to formloops 818 a having an other than parallel configuration throughout theirlength to impart special force characteristics.

Following formation of the various embodiments of the anchor mechanism18, 118, 218, 418, 518, 618, 718, 818, 1318, 1418, 1518 and braid 910,1010, 1110, 1210 as described above, it is necessary to process at leastthe tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418a, 1518 a, loops 818 a and braid 910, 1010, 1110, 1210 to have theproper shape upon deployment to subcutaneously anchor the anchoringdevice within the patient. It is similarly necessary to process theshape of the lock spring 29, 129, 229 to have a shape extending awayfrom the length of the control rod 18 b, 118 b, 218 b, the function ofwhich is explained in detail below. The shape training process alsoimparts superelasticity, as explained in detail below, to at least thetines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418 a,1518 a, loops 818 a and braid 910, 1010, 1110, 1210 assuming they aremade out of nitinol. When the integral anchor mechanism 18, 418, 518,618, 718, 818, 1318, 1418, 1518 is cut or machined from its sourcematerial and when the welded anchor mechanisms 118, 218 are assembled,the tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418a, 1518 a, loops 818 a, braid 910, 1010, 1110, 1210 and lock spring 29,129, 229 are placed in a forming jig (not shown) which holds the tines18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418 a, 1518 a,loops 818 a, braid 910, 1010, 1110, 1210 and lock spring 29, 129, 229 inthe position they will eventually be trained into. In the embodimentshown in FIG. 21 the spring portion 722 is simultaneously placed into aseparate area of the forming portion (not shown). In a preferredembodiment, the tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a,1318 a, 1418 a, 1518 a, loops 818 a, spring portion 722, lock spring 29,129, 229 and braid 910, 1010, 1110, 1210 are subjected to a temperatureof 500 degrees C. plus or minus 100 degrees C. for less than thirtyminutes, depending on the alloy chemistry, dimensions, fixturing andheat source. Different heat sources include salt bath, hot air torch andoven. A heavier and larger fixture will take a longer length of heattreatment time. Following heat treatment, the heated anchor mechanism18, 118, 218, 418, 518, 618, 718, 818, 1318, 1418, 1518 and braid 910,1010, 1110, 1210 should be quickly cooled as by an air fan. Making theanchor mechanism 18, 118, 218, 418, 518, 618, 718, 818, 1318, 1418, 1518and braid 910, 1010, 1110, 1210 from non-superelastic materials such asstainless steel, spring steel or carbon fiber is also contemplated byand therefore within the scope of the invention.

In a preferred embodiment, the anchor mechanism 18, 118, 218, 418, 518,618, 718, 818, 1318, 1418, 1518 and braid 918, 1018, 1118, 1218 isformed from nitinol wire, sheet or tubing that has been processed toexhibit superelasticity at somewhere below human body temperature(around 37 degrees C.). The invention also contemplates forming theanchor mechanism 18, 118, 218, 418, 518, 618, 718, 818, 1318, 1418, 1518and braid 918, 1018, 1118, 1218 from nitinol processed to exhibitthermal shape memory characteristics at human body temperature. Nitinolis an approximate stoichiometric alloy of nickel and titanium; however,other elements such as vanadium are sometimes added in small amounts toalter the mechanical characteristics of the alloy. Chemical compositionand processing history primarily determine the particular mechanicalproperties of a shape memory/superelastic metallic alloy. In general,such an alloy will exist in either one or the other, or combinations oftwo crystallographic phases. Austenite is the parent crystallographicphase and exists at higher temperatures. Martensite is the other phaseand is formed by either subjecting the alloy to lower temperatures or byplacing mechanical or physical stress on the alloy while it is in theaustenitic phase. Transition temperatures between these two phases canbe experimentally determined for a particular alloy. Processing historyincludes high temperature annealing as well as low temperature formingand deformation. Following standard material and processingspecifications, the transitional temperatures that define the alloy'smechanical characteristics are predictable and controllable. Standardtransitional temperature designations are given as: M_(s) for the startof the transition to the martensitic phase, M_(f) for completion of thetransition to martensite, A_(s) for the start of the transition to theaustenitic phase, and A_(f) for the completed transition to austenite.

Superelasticity is based on phase transition from austenite tomartensite. Mechanically induced phase transition from austenite tomartensite occurs when the alloy temperature is above A_(f) and aphysical restraint is applied to the alloy. As long as the restraint isin place, the portion of the alloy receiving the stress reverts to themartensitic phase, which remains as long as the stress is maintained.Unless the shape recovery limits are exceeded, when the restraint isremoved and the stress is released the alloy returns to its originalaustenitic phase and shape as long as the temperature is maintainedabove A_(f). Thus, when the austenitic, trained shape of the alloy isdeformed and held by stress in a new shape, a certain amount of force isexerted by the alloy against the restraint as it resists the new,untrained shape.

The thermal shape memory effect of these alloys has been known muchlonger than superelasticity. Thermal shape memory occurs as the resultof a piece of shape memory alloy metal being deformed while in the lowertemperature martensitic phase and then being reheated to a temperaturesomewhere above A_(s) which causes the alloy to reform in the austeniticphase. When the crystallographic nature of the alloy is completelyaustenitic, the alloy's shape returns to the previously trained shape.Shape memory training occurs when a thermal shape memory/superelasticmetallic alloy is annealed (heat treated) while restrained in a certainshape. The trained shape will then be maintained unless it is deformedwhile in the low temperature martensitic phase. Upon reheating the alloyto the austenitic phase, the original shape, which was “learned” in theannealing process, will be “remembered” and returned to. Thus,temperature change is one way of controlling the crystallographic phaseof a shape memory/superelastic metallic alloy.

One practical advantage of a shape memory/superelastic alloy overnon-superelastic materials is that it can be deformed to a far greaterdegree without taking a permanent set or kink. In the case ofsuperelastic alloys (i.e., alloys processed to exhibit superelasticityat body temperature), assuming the alloy is above the A_(f) temperature,removal of the restraint alone is sufficient to resume the original,trained shape. When the alloy is processed to have shape memorycharacteristics, the martensitic phase alloy need only be subjected totemperatures somewhere above A_(f) and the alloy will eventually returnto its original, trained shape. It is also possible to use a restraintin conjunction with alloys trained to exhibit thermal shape memorycharacteristics.

Thus, when an anchor mechanism 18, 118, 218, 418, 518, 618, 718, 818,1318, 1418, 1518 and braid 910, 1010, 1110, 1210 made of nitinol isprocessed to exhibit superelastic characteristics at somewhere belowhuman body temperature, it uses superelasticity in two different ways.First, superelasticity (stress-induced martensite) allows the anchormechanism 18, 118, 218, 418, 518, 618, 718, 818, 1318 to be repeatedlydeformed to a degree sufficient to enable it to be loaded into thechamber 14 a, 114 a, 414 a, 514 a, 614 a, 714 a, 814 a, 1314 a of theanchor sleeve 14, 114, 414, 514, 614, 714, 814, 1314 without taking apermanent set or kink. In the embodiments shown in FIGS. 24-29 a, thebraid 910, 1010, 1110, 1210 is able to be repeatedly deformed withouttaking a set or kink. While the anchor mechanism 18, 118, 218, 418, 518,618, 718, 818, 1318, 1418, 1518 is restrained by the chamber 14 a, 114a, 414 a, 514 a, 614 a, 714 a, 814 a, 1314 a, retaining band 1412 orouter sheath 1514, assuming the anchor mechanism 18, 118, 218, 418, 518,618, 718, 818, 1318, 1418, 1518 is maintained at a temperature aboveA_(f), the tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a,1418 a, 1518 a and loops 818 a contacting the inner walls (unnumbered)of the chamber 14 a, 114 a, 414 a, 514 a, 614 a, 714 a, 814 a, 1314 a,retaining band 1412 or outer sheath 1514 are exerting an amount of forceagainst the chamber 14 a, 114 a, 414 a, 514 a, 614 a, 714 a, 814 a, 1314a, retaining band 1412 or outer sheath 1514 due to the formation ofstress-induced martensite. The force exerted by the tines 18 a, 118 a,218 a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418 a, 1518 a and loops 818a, against the chamber 14 a, 114 a 414 a, 514 a, 614 a, 714 a, 814 a,1314 a, retaining band 1412 or outer sheath 1514 thus helps the anchormechanism 18, 118, 218, 418, 518, 618, 718, 818, 1318, 1418, 1518 toremain in the undeployed configuration until the physician determinesthe retention device 10, 100, 400, 500, 600, 700, 800, 1300, 1400, 1500and coupled medical device is properly introduced into the patient.

Following proper introduction, in the embodiments shown in FIGS. 1-17the tines 18 a, 118 a, 218 a, 418 a are then controllably and gentlydeployed through the ports 20, 120, 420 to secure the catheter 12, 112,412 or sheath introducer (not shown) in place below the skin for theduration of the treatment period. In the embodiments shown in FIGS.18-22 a and 30-35 the physician receives the retention device 500, 600,700, 800, 1300 in the undeployed configuration and removes the key 534,634, 734, 834, 1334 from the key aperture 536, 636, 736, 836, 1336 thuscausing proximal movement of the anchor mechanism 518, 618, 718, 818,1318 and controllable, gentle and simultaneous deployment of the tines518 a, 618 a, 718 a, 1318 a and loops 818 a through the ports 520, 620,720, 820, 1320, which is biased by the spring 522, 622, 722, 822, 1322into the default, deployed configuration.

The second way the retention device 10, 100, 200, 400, 500, 600, 700,800, 900, 1000, 1100, 1200, 1300, 1400, 1500 uses superelasticity isthat the processing of nitinol can be varied to program a desired amountof release force into the tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a,718 a, 1318 a, 1418 a, 1518 a, loops 818 a and braid 910, 1010, 1110,1210. This is advantageous because certain uses of the retention device10, 100, 200, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300,1400, 1500 may require a stronger pull strength than other uses. Byprogramming the superelastic nitinol to a greater or lesser amount ofstrength, tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a,1418 a, 1518 a, loops 818 a and braid 910, 1010, 1110, 1210 can beprogrammed that will release at a particular pull strength, rather thanbe painfully ripped out of the patient.

When the anchor mechanism 18, 118, 218, 418, 518, 618, 718, 818, 1318,1418, 1518 and braid 910, 1010, 1110, 1210 is formed to exhibit thermalshape memory characteristics at body temperature, the A_(f) isprogrammed into the alloy to be somewhere below human body temperature.The A_(s) of the anchor mechanism 18, 118, 218, 418, 518, 618, 718, 818,1318, 1418, 1518 and braid 910, 1010, 1110, 1210 is somewhere below roomtemperature prior to introduction into the patient's body.Alternatively, the anchor mechanism 18, 118, 218, 418, 518, 618, 718,818, 1318, 1418, 1518 and braid 910, 1010, 1110, 1210 (and consequentlythe whole retention device 10, 100, 400, 500, 600, 700, 800, 900, 1000,1100, 1200, 1300, 1400, 1500) is cooled to a temperature below M_(f) toplace the anchor mechanism 18, 118, 218, 418, 518, 618, 718, 818, 1318,1418, 1518 and braid 910, 1010, 1110, 1210 in the martensitic phaseprior to introduction into the patient's body. When the retention device10, 100, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400,1500 is being introduced into the body (not shown), means must be usedto maintain the temperature of the retention device 10, 100, 400, 500,600, 700, 800, 1000, 1100, 1200, 1300, 1400, 1500 below A_(s).Typically, a cold saline drip (not shown) is maintained through thechamber 14 a, 114 a, 414 a, 514 a, 614 a, 714 a, 814 a, 1314 a, theretention device 1400, 1500 or over the braid 910, 1010, 1110, 1210during the introduction procedure. Following introduction of theretention device 10, 100, 400, 500, 600, 700, 800, 900, 1000, 1100,1200, 1300, 1400, 1500 and coupled medical device at the treatment sitewithin the patient's body, the tines 18 a, 118 a, 218 a, 418 a, 518 a,618 a, 718 a, 1318 a, 1418 a, 1518 a and loops 818 a are advanced fromthe ports 20, 120, 420, 520, 620, 720, 820, 1320, 1520 of the anchorsleeve 14, 114, 414, 514, 614, 714, 814, 1314, outer sheath 1514 orreleased from the retaining band 1412 whereupon it is exposed to bodytemperature, which is above the A_(f) of the alloy. Exposure to bodytemperature raises the temperature of the alloy to a point where thetines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418 a,1518 a loops 818 a and braid 910, 1010, 1110, 1210 are in the austeniticphase, returning the tines 18 a, 118 a, 218 a, 418 a, 518 a, 618 a, 718a, 1318 a, 1418 a, 1518 a, loops 818 a and braid 910, 1010, 1110, 1210toward their original, trained shape. Because the tines 18 a, 118 a, 218a, 418 a, 518 a, 618 a, 718 a, 1318 a, 1418 a, 1518 a, loops 818 a andbraid 910, 1010, 1110, 1210 are deployed beneath the patient's skin S,they may be somewhat restrained by anatomical space limitations andtherefore may not fully assume the trained shape.

Use

Using the retention device 10, 100, 400, 500, 600, 700, 800, 900, 1000,1100, 1200, 1300, 1400, 1500 requires the physician to create anexternal incision or skin puncture proximate the internal area to beaccessed. In some cases it is also be necessary to create an incision bya scalpel or needle in an underlying vessel V or proximal an anatomicalsite to facilitate placement of retention device 10, 100, 400, 500, 600,700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500 and coupled medicaldevice (not shown). The embodiments of the retention device 10, 400shown in FIGS. 2-5 and 14-17 have the anchor sleeve 114, 414 directlyattached to a catheter 12, 412. The embodiment of the retention device10 shown in FIGS. 1 and 10-13 show the anchor sleeve 14 attached to anintroducer sheath 16. In this embodiment of the retention device 10,following introduction into a patient, a separate catheter 12 isnavigated through the lumen 16 a of the introducer sheath 16. Thecatheter 12, 112, 412 when inserted serves as a direct conduit forinfusing therapeutic solutions, draining body fluids or deliveringmechanical devices to an anatomical site. A needle (not shown) orguidewire (not shown) or dilator/sheath/guiding catheter system (notshown) is used to access the underlying vessel V or an anatomical site,the interior of which is then entered. The retention device 10, 100,400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500 andcoupled medical device is then adjusted as shown in FIGS. 1 and 36 tothe desired anatomical depth.

Following depth adjustment of the retention device 10, 100, 400, 500,600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, in theembodiments shown in FIGS. 1-17, the physician moves the control rod 18b, 118 b, 218 b, 418 b in a proximal direction by grasping and slidingthe handle 40 which controllably, gently and simultaneously moves tines18 a, 118 a 218 a, 418 a in a proximal direction. The control rod 18 b,118 b, 218 b, 418 b is prevented from excess proximal movement by thelength of the tines 18 a, 118 a, 218 a, 418 a and locked into thedesired position by the lock spring 29 rising into the internal recess32 in the chamber 14 a, 114 a, 414 a. Moving the control rod 18 b, 118b, 218 b, 418 b proximally thus results in the tines 18 a, 118 a 218 a,418 a puncturing the membranes 22 and thus exiting the anchor sleeve 14,114, 414 through ports 20, 120, 420. By means of various lock positionsavailable to the physician as a result of the lock system, the tines 18a, 118 a 218 a, 418 a can be extended to the degree desired by thephysician. Thus, the tines 18 a, 118 a 218 a, 418 a can be extended soas to define a partial arc as shown in FIGS. 1, 2 b, 6-9, 11, 13 and 15.Alternatively, if the tines 18 a, 118 a 218 a, 418 a have been trainedto assume a longer circumference, they can be more fully extended toassume a semi-circular (not shown) or even fully circular (not shown),shape. An advantage to all embodiments of the present invention hereinis that due to controllable and gentle deployment, the retention deviceis much less likely to cause internal trauma in the subcutaneousenvironments it is used in.

In the embodiments of the retention device 500, 600, 700, 800, 1300shown in FIGS. 18-23 and 30-31, in a preferred embodiment as discussedabove, the physician receives the retention device 500, 600, 700, 800,1300 in the undeployed configuration, with the seals 521, 621, 721, 821,1321 intact and with the key 534, 634, 734, 834, 1334 inserted in thekey aperture 536, 636, 736, 836, 1336 which is held in place by thelocking mechanism. Upon reaching the desired anatomical depth thephysician unlocks and removes the key 534, 634, 734, 834, 1334 whichresults in the tines 518 a, 618 a, 718 a, 1318 a and loops 818 abreaking the seals 521, 621, 721, 821, 1321 thus controllably and gentlydeploying the retention device 500, 600, 700, 800, 1300 for the durationof the treatment period.

In the embodiments shown in FIGS. 24-29 a the retention device 900,1000, 1100, 1200 can surround a medical device which defines a lumen(unnumbered) which provides communication between the interior andexterior of a patient's body. It is also contemplated (not shown) tocouple the retention device 900, 1000, 1100, 1200 to a medical device(not shown) in a manner which does not completely surround the medicaldevice (not shown). Following introduction into the patient when theretention device 900, 1000, 1100, 1200 is in the undeployedconfiguration as shown in FIGS. 25, 25 a, and 29 and upon reaching thedesired depth the physician slides the outer sheath 914, 1014, 1114,1214 in a direction so that the braid 910, 1010, 1110, 1210 assumes thedeployed configuration as shown in FIGS. 24, 26, 27 and 28. Theretention device 900, 1000, 1100, 1200 is provided with at least onelocking tab 916, 1016, 1116, 1216 which serves to maintain the retentiondevice 900, 1000, 1100, 1200 in the deployed configuration for theduration of treatment. It is also contemplated to provide a series (notshown) of locking tabs 916, 1016, 1116, 1216 extending along the lengthof the retention device which would allow the physician varying degreesof deployment.

In the embodiment of the retention device 1400 shown in FIGS. 32-33 thephysician receives the coupled medical device and retention device 1400in the undeployed configuration. The physician then creates an incisionand inserts the retention device 1400 and coupled medical device. Uponreaching the desired anatomical depth the physician slides the actuator1420 in the direction indicated in FIG. 32 which is attached to theanchor mechanism by a control member 1419. The actuator 1420 is attachedto the anchor mechanism 1418 which results in the tines 1418 a slidingin a direction allowing their escape from the retaining band 1412 thusdeploying the retention device 1400 for the duration of the treatmentperiod.

In the embodiment of the retention device 1500 shown in FIGS. 34-35 thephysician receives the coupled medical device and retention device 1500in the undeployed configuration. The physician then creates an incisionand inserts the retention device 1500 and coupled medical device. Uponreaching the desired anatomical depth the physician slides the outersheath 1514 in the direction indicated in FIG. 35. This results in thetine(s) 1518 a escaping through the port(s) 1520 allowing them to atleast partially assume their unrestrained, trained shape thus deployingthe retention device 1400 for the duration of the treatment period.

The embodiments of the retention device 10, 100, 400, 500, 600, 700,800, 900, 1000, 1100, 1200 1300, 1400, 1500 are preferably integrallyattached to a medical device such as a catheter, sheath introducer,feeding tube, ostomy bag, pacing lead or other device intended fortemporary but extended implantation in a patient. In another embodiment,the retention device 10, 100, 400, 500, 600, 700, 800, 900, 1000, 1100,1200, 1300, 1400, 1500 is contemplated to be separately attachable tothe above listed medical devices by such means as (but not limited to)press fit, adhesives, hook and loop fastener material, snaps, retainingrings, thermal melting techniques, sonic welding, crimping, heat shrink,mechanical fasteners, or a sheath introducer.

Removing the retention device 10, 100, 400 from the patient involvesunlocking the lock system by depressing the lock spring 29 from therecess 32 with the key 34 and moving the control rod 18 b, 118 b, 218 b,418 b via the handle 40 in a distal direction. This results in the tines18 a, 118 a 218 a, 418 a simultaneously moving in a distal directionwhereby the tines 18 a, 118 a 218 a, 418 a reenter the anchor sleeve 14,114, 414 through the ports 20, 120, 420 whereby the retention device 10,100, 400 is removed from the patient following completion of the courseof treatment.

Removing the retention device 500, 600, 700, 800, 1300 from the patientat the termination of treatment, the physician reverses the introductionprocedure by re-inserting the key 534, 634, 734, 834, 1334 into therespective key aperture 536, 636, 736, 836, 1336. This results in theanchor mechanism 518, 618, 718, 818, 1318 and tines 518 a, 618 a, 718 a,1318 a or loops 818 a simultaneously retracting into the chamber 514 a,614 a, 714 a, 814 a, 1314 a which allows removal of the retention device500, 600, 700, 800, 1300 from the patient.

Removing the retention device 900, 1000, 1100, 1200 from the patient atthe termination of treatment requires the physician to first unlock thelocking tab 916, 1016, 1116, 1216. The physician next moves the outersheath 914, 1014, 1114, 1214 in a direction allowing the braid 910,1010, 1110, 1210 to resume its undeployed configuration, allowingremoval of the retention device 900, 1000, 1100, 1200 and coupledmedical device (not shown).

Removing the retention device 1400 from the patient requires thephysician to re-insert the actuator 1420 into the actuator groove 1414and exert an amount of force necessary to slide the anchor mechanism1418 into the position shown in FIG. 32. This simultaneously restrainsthe tine(s) 1418 and thus, the retention device 1400 is returned to itsundeployed configuration. The physician is then able to remove theretention device 1400 and coupled medical device from the patient.

Removing the retention device 1500 from the patient requires thephysician to re-slide the outer sheath 1514 into the position shown inFIG. 34. This simultaneously restrains the tine(s) 1418 and thus, theretention device 1500 is returned to its undeployed configuration. Thephysician is then able to remove the retention device 1500 and coupledmedical device from the patient.

1. A device for coupling with a catheter device and for subcutaneouslyanchoring the catheter device to a patient, comprising: a catheterretainer including a catheter-receiving channel extending in alongitudinal direction to a distal opening, the catheter-receivingchannel being configured to releasably engage with an outer surface of aremovably coupled catheter device; and a subcutaneous anchor assemblythat is spaced apart from the catheter-receiving channel and thatincludes: a longitudinal extender assembly secured to the catheterretainer and extending in a direction that is generally parallel to thelongitudinal direction of the catheter-receiving channel, and first andsecond curved anchors extending outwardly away from a distal region ofthe longitudinal extender assembly, wherein when the removably coupledcatheter device is positioned through a skin puncture, the first andsecond curved anchors are insertable through the same skin puncture tosubcutaneously deploy the first and second curved anchors for tissueengagement along an underside of a skin layer so that a free end of thefirst curved anchor extends generally oppositely away from a free end ofthe second curved anchor, wherein the first curved anchor includes afirst convexly bowed portion extending lengthwise toward the free end ofthe first curved anchor such that the first convexly bowed portion facesproximally toward the catheter retainer, wherein the second curvedanchor includes a second convexly bowed portion extending lengthwisetoward the free end of the second curved anchor such that the secondconvexly bowed portion faces proximally toward the catheter retainer. 2.The device of claim 1, wherein the first and second curved anchors arecapable of repeatedly moving between a first configuration in which thefirst and second curved anchors are positioned for insertion through thesame skin puncture and a second configuration in which the first andsecond curved anchors extend outwardly away from one another ingenerally opposite directions.
 3. The device of claim 1, wherein thefirst and second curved anchors comprise a nitinol material.
 4. Thedevice of claim 1, wherein the first and second curved anchors comprisestainless steel.
 5. The device of claim 1, wherein the subcutaneousanchor assembly is movable relative to the catheter retainer.
 6. Thedevice of claim 1, wherein the longitudinal extender assembly comprisesa rod.
 7. The device of claim 6, wherein the rod of the longitudinalextender assembly is an actuator rod that is adjustable relative to thecatheter retainer.
 8. The device of claim 1, wherein the longitudinalextender assembly is housed inside the catheter retainer.
 9. The deviceof claim 1, wherein the free end of the first curved anchor terminatesat a dull or rounded tip, and wherein the free end of the second curvedanchor terminates at a dull or rounded tip.
 10. The device of claim 1,wherein the first convexly bowed portion of the first curved anchor andthe second convexly bowed portion of the second curved anchor facetoward the underside of the skin layer when the first and second curvedanchors are subcutaneously deployed.
 11. A device for coupling to amedical device and for subcutaneously anchoring the medical device to apatient, comprising: a medical device retainer including a channelextending to a distal facing opening and being configured to releasablyengage with an outer surface of a medical device; and an anchormechanism contacting the medical device retainer and being spaced apartfrom the channel of the medical device retainer, the anchor mechanismincluding: a longitudinal extender apparatus secured to the medicaldevice retainer, and first and second curved anchors extending outwardlyaway from a distal region of the longitudinal extender apparatus, eachof the first and second curved anchors terminating at a dull or roundedtip, wherein the first and second curved anchors are configured to movefrom a first position to a subcutaneously deployed position in which thefirst and second curved anchors are adapted to engage tissue along anunderside of a skin layer, wherein the first curved anchor includes afirst lengthwise convexly curved portion extending toward the free endof the first curved anchor such that the first lengthwise convexlycurved portion bows toward the medical device retainer, and wherein thesecond curved anchor includes a second lengthwise convexly curvedportion extending toward the free end of the second curved anchor suchthat the second lengthwise convexly curved portion bows toward themedical device retainer.
 12. The device of claim 11, wherein the firstand second curved anchors are capable of repeatedly moving between thefirst position in which the first and second curved anchors are arrangedfor insertion through a skin puncture and the subcutaneously deployedposition in which the first and second curved anchors extend outwardlyaway from one another in generally opposite directions.
 13. The deviceof claim 12, wherein when the first and second curved anchors arepositioned in the subcutaneously deployed position, a space between thefree ends of the first curved anchor is greater than the space betweenthe free ends of the first curved anchor when the first and secondcurved anchors are positioned in the first position.
 14. The device ofclaim 11, wherein when the medical device is releasably engaged by themedical device retainer and inserted through a skin puncture, the firstand second curved anchors are insertable through the same skin punctureto subcutaneously deploy the first and second curved anchors for tissueengagement along the underside of the skin layer.
 15. The device ofclaim 11, wherein the first and second curved anchors comprise amaterial selected from the group consisting of stainless steel andnitinol.
 16. The device of claim 11, wherein the anchor mechanism ismovable relative to the medical device retainer.
 17. The device of claim11, wherein the longitudinal extender apparatus comprises a rod.
 18. Thedevice of claim 17, wherein the rod of the longitudinal extenderapparatus is an actuator rod that is adjustable relative to the medicaldevice retainer.
 19. The device of claim 11, wherein the longitudinalextender apparatus is housed inside the medical device retainer.
 20. Thedevice of claim 11, wherein the first lengthwise convexly curved portionof the first curved anchor and the second lengthwise convexly curvedportion of the second curved anchor face toward the underside of theskin layer when the first and second curved anchors are subcutaneouslydeployed.